Mitsubishi Montero (2004+). Manual - part 261

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-531

STEP 4. Check the evaporative emission ventilation 
solenoid using scan tool MB991958 (Actuator test item 29).

CAUTION

To prevent damage to scan tool MB991958, always turn the 
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
(1) Connect scan tool MB991958 to the data link connector.

(2) Disconnect hose S from the evaporative emission 

ventilation solenoid and connect a hand vacuum pump.

(3) Turn the ignition switch to the "ON" position.
(4) Set scan tool MB991958 to actuator test mode.

Item 29: Evaporative Emission Ventilation Solenoid Valve. 

While the evaporative emission ventilation solenoid is 
energized, operate the hand vacuum pump and confirm 
that solenoid holds vacuum.

• While the evaporative emission ventilation solenoid 

is energized, operate the hand vacuum pump and 
confirm that solenoid holds vacuum.

(5) Turn the ignition switch to the "LOCK" (OFF) position and 

disconnect scan tool MB991958.

(6) Disconnect the hand vacuum pump and connect hose S to 

the evaporative emission ventilation solenoid.

Q: Does the evaporative emission ventilation solenoid hold 

vacuum?
YES : Go to Step 5.
NO :  Replace the evaporative emission ventilation 

solenoid. (Refer to GROUP 17, Evaporative Emission 
Canister and Fuel Tank Pressure Relief Valve 

P.17-72

). Go to Step 18.

AC306409AF

MB991911

MB991824

MB991827

AC101769

HOSE S

AC

EVAPORATIVE EMISSION

VENTILATION SOLENOID

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-532

STEP 5. Check for leaks in the evaporative emission 
system hose S.

Perform a leakage test with a hand vacuum pump on hose 
S.

Q: Does hose S hold vacuum?

YES : Go to Step 6.
NO :  Replace hose S. Go to Step 18.

STEP 6. Check for leaks in the evaporative emission 
system hose E.

Perform a leakage test with a hand vacuum pump on hose 
E.

Q: Does hose E hold vacuum?

YES : Go to Step 7.
NO :  Replace hose E. Go to Step 18.

AC102452

HOSE S

AC

OVER VENT

VALVE

MODULE

AC101772

HOSE E

AC

EVAPORATIVE EMISSION

CANISTER

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-533

STEP 7. Pressure test the evaporative emission system 
lines between hose F and R.
(1) Disconnect hose F from the evaporative emission canister 

and plug hose F securely.

(2) Confirm that the evaporative emission system pressure 

pump (Miller number 6872A) is operating properly. Perform 
the self-test as described in the manufacturer's instructions.

(3) Remove the fuel cap.

(4) Connect the evaporative emission system pressure pump 

to the fuel tank filler tube.

(5) Pressure test the system to determine whether any leaks 

are present.
NOTE: The "Pressure test" in this procedure refers to the 
I/M240 Simulation Test. The eight steps of this test are 
described in the manufacturer's instructions for the evapo-
rative emission system pressure pump, Miller number 
6872A.

(6) Disconnect the evaporative emission system pressure 

pump and reinstall the fuel cap.

(7) Connect hose F to the evaporative emission canister.
Q: Is the evaporative emission system line free of leaks?

YES : Go to Step 15.
NO :  Go to Step 8.

STEP 8. Check for leaks in the evaporator line hose F.
(1) Remove the fuel tank filler tube protector. (Refer to GROUP 

13B, Fuel Tank 

P.13B-8

).

(2) Disconnect hose F from the evaporative emission canister 

and plug hose F securely.

(3) Disconnect hose G from the evaporative emission canister 

side, and connect a hand vacuum pump.

(4) Apply vacuum with the hand vacuum pump and confirm that 

the vacuum holds.

(5) Disconnect the hand vacuum pump and connect hose F 

and G. 

Q: Does hose F hold vacuum?

YES : Go to Step 9.
NO :  Replace hose F and reinstall the fuel tank filler tube 

protector. (Refer to GROUP 13B, Fuel Tank 

P.13B-8

). 

Go to Step 18.

AC102602 AC

HOSE F

ACX01358

AC101767 AC

HOSE F

HOSE G

MULTIPORT FUEL INJECTION (MFI) DIAGNOSIS

TSB Revision

MULTIPORT FUEL INJECTION (MFI)

13A-534

STEP 9. Check for leaks in the evaporative emission 
system hoses G through N.
(1) Remove the fuel tank filler tube. (Refer to GROUP 13B, 

Fuel Tank 

P.13B-8

).

(2) Perform a leakage test with a hand vacuum pump on each 

hose from hose G to N.

Q: Does the hoses hold vacuum?

YES : Go to Step 10.
NO :  Replace any damaged hose, and reinstall the fuel 

tank filler tube and the fuel tank filler tube protector. 
(Refer to GROUP 13B, Fuel Tank 

P.13B-8

). Go to 

Step 18.

STEP 10. Check the check valve A.
(1) Check valve A is a one-way check valve.

(2) Check valve A should allow air to flow in only one direction.
Q: Does check valve A allow air to press in one direction 

only?
YES : Go to Step 11.
NO :  Replace check valve A, and reinstall the fuel tank filler 

tube and the fuel tank filler tube protector. (Refer to 
GROUP 13B, Fuel Tank 

P.13B-8

). Go to Step 18.

AC102673 AC

HOSE G

HOSE L

HOSE M

HOSE N

AC102646 AC

HOSE K

HOSE I

HOSE H

HOSE J

AC102646 AD

CHECK
VALVE A

AC002076 AB

CHECK VALVE A